Composites of polyethylene oxide (PEO)/NH4I Polymer electrolyte dispersed with semiconductors PbS, US and PbxCd1-xS in different weight ratios have been prepared and characterised. Relevant amount of Pb and/or Cd acetates were added to a Viscous solution of polymer PEO/NH4I complex. On sulfuration by bubbling H2S through it, the in situ formation and dispersal of PbS, US or PbxCd1-xS resulted. Solution casting gave the "semiconductor-dispersed polymer electrolyte" (SPDE) membranes with 10-20% of electronic conductivity depending upon the preparatory conditions.